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| CfA Colloquium Schedule Fall 2011 | ||
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15 September 2011Speaker: Lisa Kewley (IfA, Hawaii) Title:Galaxy Formation and Evolution through Metals Abstract: Chemical abundances in galaxies provide a fossil record of previous generations of star formation, modulated by galactic-scale gas flows. I will present the latest results from our investigation into the chemical evolution of galaxies, both locally, and at high redshift. Theory predicts that as a merger progresses, galaxy disks become disrupted by tidal effects, causing large radial gas flows toward the central regions where kpc-scale starbursts and AGN may be fueled. Isolated disk galaxies have strong chemical abundance gradients that may become disrupted during a merger. We have conducted the first investigation into chemical abundance gradients across the merger sequence. We show that abundance gradients evolve dramatically with merger progress, providing a smoking gun for galactic-scale gas flows in merging galaxies. Moving out in redshift, I present recent results from our investigation into the cosmic chemical history of galaxies. We have measured the chemical abundances for an unprecedented number of galaxies to z~1, finding little evolution between z~1 and the present day. At higher redshift, we exploit the power of gravitational lensing to investigate the chemical evolution in galaxies between 1 < z < 3. We have measured the first metallicity gradient in a normal spiral galaxy at z~2, showing a steeper gradient than observed in local spiral galaxies. I will discuss the implications of this result and the future of this field with the next generation of telescopes.
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